Composition containing castor oil derivative



a ne-.11... 14, 1936 courosmox Merlinlhrtin Brubaher signer to E. I. du Pont de GON'I'AININ G CASIO! OIL DERIVATIVE 11, Del. a of Delaware No Drawing. Application sin-n 11. ms, SerialN 9 claims. (on. 134-242) This invention relates to film forming compositions and more particularly to improved cellulose derivative compositions.

Pyroxylin films are brittle and in order to overcome this difliculty various softening agents have been added to nitrocellulose coating compositions for the purpose of imparting flexibility to the films resulting from these coating compositions.

I have found, however, that certain derivatives of hydrogenated castor oil furnish improved softening agents. The use of the acetyl derivative of hydroxystearin (the main constituent of hydrogenated castor oil) as a softening agent has been proposed, but insofar as I am aware the improved products resulting from the' esterification of hydrogenated castor oil with acids of the type disclosed herein, are new.

This invention has as an object the production of new and useful compositions of A further object is to provide nitrocellulose coating compositions in which these esters 'are incorporated for the purpose of yielding films which will not become rancid with age, will retain their flexibility upon aging, and which have a high exudation temperature.

The above objects are accomplished by the following invention in which an oily softener consisting of the product obtained by reacting hydrogenated castor oil with organic polybasic acids A in such proportion as to yield a product soluble V in organic solvents.

Castor oil consists chiefly (about of the tri-glyceride of ricinoleic acid, which may be exa pressed by the following formula:

Castor oil turns rancid because of oxidation which occurs at the double bonds and when such rancidification occurs, a brittleness of the manlin film softened with castor oil develops. Removal of the double bonds by hydrogenation, whichmaybeeirectedintheknownmannerby using a nickel catalyst below 200' 0., converts the i lyceride or ricinoleic acid into the triglyceride of hydroxy stearic acid:

o Monowm-omwmmom-mm i Triglyceride of hydroxy stearic acid This product, however, is a hard white wax melting at 86 C. and incompatible with nitrocellulose. Hydrogenated castor oil cannot, therefore, without further modification, be used as a film softening agent. This material still contains the hydroxyl groups originally present in the ricinoleic acid molecule, and I have discovered that when these hydroxyl groups are esterifled with organic polybasic acids, as described herein, liquid to resinous products result which are readily compatible with nitrocellulose.

I have found that very valuable softening agents for nitrocellulose films may be obtained 25 by esterifying hydrogenated castor oil, 1. e., the tri-glyceride of hydroxy stearic acid, with aromatic or aliphatic diabasic acids in particular, as exemplified by the following examples.

Example I Example If A mixture of 700 parts of hydrogenated castor oil andlliparts of succinic acid is heated with or without stirring or blowing at 225 C. for 8% hours, or until the acid number has reached a value of, roughly, 25.0. .The product is a very viscous It may be used as such without further purification Inlikemannerthemaybecon-so mentioned in Examples I and 11. Other examples of suitable polybasic aromatic acids are trimesic, salicyl-acetic, chlorophthalic, trimellitic, naphthalic, and diphenic acids. Further examples of other suitable aliphatic polybasic acids are citric, tartaric, fumaric, dilactylic, tricarballyic' and sebacic acids. In general, all polybasic carboxylic acids whether aromatic, aliphatic or heterocyclic, e. g. quinolinic, may be used. .I desire it to be understood that the'polybas'ic acidsvreferredv to in the claims include either the acid or the an-' hydride thereof.

' Although these esters are most conveniently prepared by heating the hydrogenated castor oil with the acid, any of the well known methods of esterlfication may be used, as forinstance by reacting the hydrogenated castor oil with an acyl halide or an acid anhydride. Furthermore, the hydrogenated castor oil may mixtures of different polybasic acids, or with mixtures of mono and polybasic acids, and the esterification may be carried out in the presence of a non-reactive solvent, as in my co-pending application (Serial No. 421,585 filed January 17, 1930) In general the reaction may be carried out at temperatures between 150 and 275 C. but it is preferred to operate at 210-250 C. Furthermore thesee'sters can be prepared by the hydrogenation of polybasic acid esters of castor oil which may be done in solution, e. g. in decalin, if necessary.

A typical example of a nitrocellulose composition containing my improved softeners and suitable for use in coating fabrics for'the preparation of artificial leather is as follows:

Example 111 Parts by weight Nitrocellulose seconds viscosity) 1 Phthalate of hydrogenated castor oil 1.50 Pigment 1 Solvent 4.25

A lacquerffor wood, metal, etc., is as follows:

Example IV Parts by weight Nitrocellulose (V2 second viscosity) 12 Damar gum I 3 ,Dibutyl phthalate 4 Phthalate of hydrogenated castor oil 2.6

In these examples the softening agent indicated may be replaced with other polybasic acid derivatives of hydrogenated castor oil, such as the succinic acid derivative of Example II.

For use as softeners in films for artificial leather coatings, the esters of aliphatic polybasic acids produce films having relatively high exudation temperatures. While the softening agents produced from the polybasic aromatic acids do not yield films having as high an exudation temperature as those produced with aliphatic acids,

produce softenthe aromatic acids do,however, ing agents, which, because of their higher viscosity, lend toughness The viscosity and consequent toughening property increases in general with the basicity of the.

the tribasic acids, for example, being more acid, efiective in this respect than the dibasic' acids. In nitrocellulose coatings for artificial leather, in-' crease in viscosity is, however, undesirable be yond a certain point and the dibasic acids as esterifying agents are preferred as a rule.

Mixtures of the various-softening agents can be used and different ratios of softener, pyroxylin,

terials.

be esterified with to the nitrocellulose film.

pigment and gumvmay be used in the coating compositions as will be readily understood by those skilled in the art.

The present invention finds its most important I use in the preparation of such compositions as are used in the coating of fabrics for the producucts, or certain of the esters not so desirable in I artificial leather coatings. Obviously, many other uses will suggest themselves to those skilled in the art, such as adhesives, lubricants, fluids for hydraulic shock absorbers, and impregnating agents for paper, fabric and other porous ma- In many cases it will be found that esteriflcation with polybasic acids, ifcarried too far, will produce gelled or insoluble products these are unsuitable for the purpose of the present invention. The gelation can be avoided by heating at a lower temperature for a shorter period of time, or by including monohydrlc alcohols and/or monobasic acids as additional reaction components.

Films flowed from nitrocellulose coating compositions containing my improved softening agents have been found to withstand, after aging, either the same number of bends, or a greater number than they would initially and no rancidity development could be detected after aging. In certain of these softeners greater toughness and a higher exudation temperature is imparted to the pyronlin film. The exudation temperature of the film is as great as, and is usually greater than, one in which castor oil is the softener.

The present invention is distinguished from the application of L. P. Hubbuch, Serial No. 604,670, now Patent 2,015,145 and from my application, Serial No. 604,665, filed of evendate herewith in that both of these applicationsrequire the use of a polyhydric alcohol, the former application claiming monobasic acid esters of alcoholized hydrogenated castor oil, or more specifically monobasic acid esters of mono and/or diglycerides-of. hydrogenated castor ofl, the ,latter application claiming hydrogenated fatty oil modified polyhydric alcohol-polybasic acid resins produced by reacting a polyhydric alcohol, hydrogenated fatty oil, and a polybasicacid.

Altho the use of our new esters has been described with particular reference to nitrocellulose, other cellulose derivatives such as the acetate, propionate, aceto-butyrate, the ethyl or benzyl ethers, etc., may be used with these new products in coating, plastic, impregnating, or adnot limit myself to as delose derivative and the oily reaction product of polycarboxylic acid and hydrogenatedcastor oil consisting essentially of hydroxy stearin.

2. A composition of matter comprising a cellulose derivative and the oily reaction product of a dicarboxylic acid and hydrogenated castor oil consisting essentially of 'hydroxy vstearin.

3. A composition of matter comprising a cellulose derivative and the oily reaction product of goo-Moe I 3 phthalic acid and hydrogenated castor oil consisting essentially 0! hydroxy stearin.

4. A composition of matter comprising a cellulose derivative and the oily reaction product of an aliphatic discarbonlic acid and hydrogenated castor oil consisting essentially 0! hydroxy stearin.

I 5. A composition of matter comprising a cellulose derivative and the oily reaction product of succinic acid and hydrogenated 'castcr oil consisting essentially oi hydroxy stearin.

6. The composition set forth in claim 1 in which the cellulose derivative is nitrocellulose.

'I. The composition set forth in claim 2 in which the cellulose derivative is nitrocellulose.

8. The composition set iorth in claim 3 in which 5 the cellulose derivative is nitrocellulose.

9. The composition set iorth in claim 5 in which the cellulose derivative is nitrocellulose.-

mm: mm 312mm. 10

CERTIFICATE OF CORRECTION.

Patent No. 2,027,466. January'l i; 1956.

MERLIN MARTIN BRUBAKER.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as followe: Page 1, second oolumn, line 34, for the numeral "255" read 225; and that the said Letter}? Patent should be read' with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 21st day of April, A. D. 1936.

' Leslie Frazer (Seal) Acting Commissioner of Patents. 

